This invention relates to an engine for small watercraft capable of discharging water collected in a crank chamber of a two-cycle engine driving a propeller shaft.
One type of small watercraft adapted to be driven by a driver in a standing or sitting position for movement on the water may be constructed such that it can be readily righted when turned over.
However, when the small watercraft turns over, water might enter into the engine through a suction inlet port opening in the engine cover for the engine and find its way into the crank chamber of the engine through the air cleaner. When the engine is constructed such that cooling water is led to the exhaust muffler after cooling the engine, the injected water might flow backwardly when the watercraft turns over laterally and enter the crank chamber via the combustion chamber.
Once water enters the crank chamber, the engine would stop and difficulty would be experienced in restarting it.
Engines for a small watercraft of the prior art are constructed such that the water collected in the crank chamber possesses a problem which is hard to solve. Thus, when water entered the crank chambers, it has hitherto been usual practice to remove the engine from the engine housing and start it by turning it through 180 degrees after removing the ignition plug therefrom, so as to discharge the water from the crank chamber.
The process described hereinabove is troublesome and makes it impossible to restart the engine quickly because the engine should be removed from the engine housing and turned through 180 degrees. Moreover, when the engine is mounted in the engine housing again, it is necessary to effect centering of the crankshaft of the engine with respect to the propeller shaft. Thus, the process is very low in operability.